Structural elements for false ceilings are known, consisting of profile bars of inverted T-shape provided at their ends with hooks formed either directly from the central web of the T profile bar or from inserts which are formed separately for application to each profile during its production.
Said profile bars are connected together to form a lattice structure which by means of steel ties or cables is generally suspended at its top from the ceiling, their horizontal flanges lowerly supporting panels, staves and anything else required to form the false ceiling.
Such structural elements are currently formed using single-die presses, ie presses comprising a die of dimensions corresponding to the length of the profile bar to be formed, which is housed within the press and on which the various operations are carried out, possibly in a single step but more generally in several steps, and always within the actual die in which the bar is positioned. Said die is provided with a plurality of punches which are operated in sequence to effect on the bar such operations as perforating; drawing, crimping, etc.
These known single-die presses have however certain drawbacks, namely:                poor flexibility in that for each size (length) of profile bar the press requires a particular die which has to be changed each time the profile bar is to be modified or following any change in dimensions or type of operation,        they require a large number of different dies depending on the type of hook, the length of the profile bars and the type of operation to be carried out,        they immobilize capital,        they occupy considerable storage space.        